Method of monitoring the filling of a washing machine drum with water

ABSTRACT

A method of monitoring a washing machine aggregate for impermissible or atypical movements during a first phase of a washing program while water is being filled into the aggregate and for discontinuing the filling upon detection of such movement as may result, for instance, from the presence of a child or animal in the aggregate.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention, in general, relates to a method of monitoring the fillingof a washing machine drum with water and, more particularly, to a methodof the kind referred to in a washing machine provided with a housing, awashing aggregate including a tub mounted for oscillatory movementwithin the housing and including a drum rotatably mounted therein forreceiving laundry and/or washing fluid and sensor for detecting amovement of the aggregate and for discontinuing any washing program uponrecognition of an impermissible movement during a first phase of thewashing program, with the drum being either stationary or rotating toand fro during the first phase.

2. The Prior Art

Such a method is generally known from the disclosure of Patent Abstractsof Japan No. JP 2004065408 A. It is provided with a sensor for detectingan impermissible movement of the drum or of the washing fluid tub duringan idle time between initiation and execution of the washing program. Asimilar method has been disclosed by Patent Abstracts of Japan No. JP10179978 A. A motion sensor or acceleration sensor mounted at an upperportion of the tub recognizes a detected movement as originating from achild within the drum. Its proper function is, however, dependent uponmovements of the child.

Yet another method has been disclosed by German Laid-open PatentSpecification No. DE 42 25 769 A1. In this case, weight present withinthe drum is detected by a weight sensor prior to initiation of a washingprogram and if the weight exceeds a predetermined threshold value thewashing program is either not initiated or an alarm is activated. Themethod is suitable only for washing loads of no more than 4.5 or 5 kg ofdry laundry, however. The method is unsuitable for larger washingmachines with capacities of 8 kg of dry laundry because it cannotdistinguish whether the detected weight originates with the permissiblelaundry in the drum or with a child of substantially the same weight.

OBJECT OF THE INVENTION

It is an object of the invention with simple means to improve the safetyof, and thus protect from possible harm, a child present in the drum,accidentally or otherwise.

SUMMARY OF THE INVENTION

In the accomplishment of these and other objects, the invention providesa method of monitoring the filling of a washing machine drum with waterand, more particularly, to a method of the kind referred to in a washingmachine provided with a housing, a washing aggregate including a tubmounted for oscillatory movement within the housing and including a drumrotatably mounted therein for receiving laundry and/or washing fluid andsensor for detecting a movement of the aggregate and for discontinuingany washing program upon recognition of an impermissible movement duringa first phase of the washing program, with the drum being eitherstationary or rotating to and fro during the first phase, the methodincluding the step of introducing a predetermined quantity of water intothe tub during the first phase of the washing program.

Further features of the novel program will become apparent as thedescription of the invention unfolds hereafter.

The advantage derived from the method in accordance with the inventionis that a very reliable recognition of a child or pet within the drum ofa washing machine results in high safety and the prevention of possiblehazards and injuries. A further advantage is that the method isextremely simple and cost-efficient, since it depends upon theutilization of sensors and/or detectors for the weight of laundry or outof round movement of the drum which are standard features of currentwashing machines. The method is advantageously characterized the factthat a child sleeping in the drum will be woken and stimulated to move.This is accomplished in a simple manner by water, in particular coldwater being introduced into the tub and drum after initiation of awashing program, i.e. after actuating a start button. A child resting orsleeping in the drum will thus be woken by the entering water andstartled such that because of the unpleasant wet feeling it will move.Since during this first phase the drum is not yet moved by its drive,any detected movement will result in termination of a selected washingprogram. In a practical embodiment, the first phase of the washingprogram may include movements of the drum, especially rocking motions,in order effectively to induce any child in the drum to move. There areno possibilities of the child being hurt or injured by such movements.

After recognition of a child because of a movement of the drum in itsidle phase, a visible or audible alarm may be issued or the loading doormay be automatically unlatched and opened.

The quantity and temperature of the water are limited so that any childin the drum can neither drown nor be injured in any other way. To thisend, the quantify of introduced water is only a partial portion of thewashing liquid required for executing a washing program.,

Persons skilled in the art will understand that during the first phaseof a washing program no detergents or other laundry agents are admittedto the tub and the drum. Thus, in an advantageous embodiment of theinvention no laundry detergent or other substance is added to the waterduring an initial phase of the washing program. The water is caused tocircumvent the detergent compartment of the washing machine during itsinitial feeding into the tub.

The duration of the first phase of the washing program is such that atthe beginning of the first phase water is fed in, e.g., for about 30seconds and that the machine remains idle thereafter, for instance forabout 60 seconds prior to commencement of the second phase whichincludes the washing program proper. During the entire first phase, i.e.for about 90 seconds, the any movement of the washing aggregate or ofdrum will be monitored and upon detection of any movement caused by achild the second phase of the washing program will not be commenced.

Alternatively, the first phase may be terminated or interruptedimmediately upon detection of impermissible movements in order toshorten the first phase and any time a child may be in the tub or drumand thus to reduce or prevent any traumatic experience.

Since the movement of the washing aggregate or of the drum caused by thewater flowing in is clearly different from a movement caused by a child,faulty interpretations are avoided.

In a useful embodiment of the invention, a path sensor is used fordetecting the movement. Such sensors are customarily provided betweenthe washing aggregate and the housing. However, the detection may alsobe brought about by other means, such as, for example, tachometers,motion sensors, acceleration meters, pressure gages, power sensors ortorsion sensors.

Advantageously, the detection or recognition of a child beingimpermissibly present in the drum and subject to harm therein, is fed toan evaluation unit.

The method is not limited in its application to the recognition of achild or animal being present in the drum of a washing machine, but itmay be utilized to equal advantage to the detection of dogs, cats,rabbits birds or anything else which causes a washing machine drum tomove impermissibly at a time when it should be stationary.

DETAILED DESCRIPTION OF THE SEVERAL DRAWINGS

The novel features which are considered to be characteristic of theinvention are set forth with particularity in the appended claims. Theinvention itself, however, in respect of its structure, construction andlay-out as well as its manufacturing techniques, together with otheradvantages and objects thereof, will be best understood from thefollowing description of preferred embodiments when read in connectionwith the appended drawings, in which:

FIG. 1 is a schematic presentation of the arrangement of a washingaggregate within a housing;

FIG. 2 exemplarily depicts a diagram of the condition of a washingprogram in a normal situation; and

FIG. 3 exemplarily depicts a diagram of the condition of a washingprogram in a faulty situation.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS.

As schematically shown in FIG. 1, the washing aggregate or washing fluidtub 2 is suspended by springs 3 for oscillatory movements within thehousing 1 of a washing machine housing from housing components notshown. The washing aggregate consists of a washing fluid tub 2 and adrum 16 mounted for rotary movement within the tub 2. Rotary movement isat times imparted to the drum 16 by a motor 19 by way of a belt drive.Shock absorbers 4 are provided to prevent excessive oscillations in caseof imbalanced loads in the drum 16. A path sensor 6 detects not only anyimbalance or the condition of a load within the drum 16 but alsomovements of the washing aggregate 2 or of the drum 16. An evaluationunit 5 is connected by way of a connecting line 7 to the path sensor 6to receive from it any detected values. A detergent chamber 15 isprovided to receive and during a washing operation to dispensepredetermined amounts of detergent and/or other washing agents. Aloading opening 17 is closed after loading the laundry into the drum 16and before starting a selected washing program.

FIG. 2 schematically depicts the chronological sequence of a washingprogram. During an idle phase 8, the washing machine is either switchedoff or the user has nor yet started the washing program. At time t=5 thestart button 9 is actuated which activates the first phase 10 of thewashing program. During the first phase, means such as the path sensor 6and an evaluation circuit 5 are activated for detecting any movement ofthe washing aggregate or of the drum 16. In addition, water, moreparticularly cold water, is fed to the washing fluid tub and into thedrum 16 at the beginning of the first phase. The time during which wateris fed and the quantity of the water are measured such that while achild or pet possibly present in the drum 16 will be drenched and wokenand startled to move, it will not drown or undercooled. If noimpermissible movement of the washing aggregate or of the drum 16 isdetected during the first phase, the second phase 12 will succeed thefirst phase 10 at time t=8. The second phase includes the actual washingprogram selected by the user. The second phase 12 and the washingprogram which includes washing, rinsing and spinning cycles with strongdrum movements will run completely until its programmed termination 13.

FIG. 3 by way of example depicts the chronological sequence of a programabortion 14. In this case, movement of the washing aggregate 2 wasdetected during the first phase 10 which led to premature termination 14of the program at time t=8. However, it would also be possible at timet=7, immediately upon detection of an impermissible movement,prematurely to abort 14 a and terminate the first phase 10. Uponrecognition of an impermissible movement and following program abortion14, 14 a, an audible or visible alarm 18 may be issued and/or theloading opening 17 may be automatically unlatched or opened.

1. A method of operating a washing machine comprising a housing, a:washing aggregate suspended therein for oscillating movements, a washingdrum mounted for motor-induced rotational movement within the aggregatefor receiving laundry and washing fluid and means responsive to movementof the washing aggregate during a first phase of the washing programwhile the drum is in an idle state and cooperating with an evaluationcircuit for discontinuing a washing program upon recognition of animpermissible movement of the aggregate by the evaluation circuit,comprising the step of filling a predetermined quantity of water intothe tub during the first phase of the washing program.
 2. The method ofclaim 1, wherein the predetermined quantity of water corresponds to apartial portion of the washing fluid.
 3. The method of claim 2, whereinthe washing machine further comprises a detergent dispensing chamber,further including the step of circumventing the detergent dispensingchamber when introducing the predetermined quantity of water.
 4. Themethod of claim 1, wherein the movement of the aggregate during thefirst phase is detected bay a path sensor.
 5. The method of claim 1,wherein movement of the washing aggregate is detected by a sensorresponsive to at least one of number of rotations, movement,acceleration, pressure, force and torsion.
 6. The method of claim 1,further including the step of immediately upon recognizing animpermissible movement of the aggregate the first phase is prematurelydiscontinued.
 7. The method of claim 6, further including the step ofautomatically unlatching the loading opening upon recognizing animpermissible movement of the aggregate.
 8. The method of claim 6,further including the step of automatically opening the loading openingupon recognizing an impermissible movement of the aggregate.
 9. Themethod of claim 1, further including the step of issuing an alarm uponrecognizing an impermissible movement of the aggregate.
 10. The methodof claim 9, wherein the alarm is an audible one.
 11. The method of claim9, wherein the alarm is a visible one.